Climate change is real, and we are living with its effects every day. Some parts of the world are suffering more than others, as those who live in the most fragile ecosystems have become the canaries in the global coal mine. But, as our weather patterns become more extreme, the earth and the crops we grow are showing signs of the strain.
Several recent studies have looked at the effect of climate change on the five most important food crops in the world—rice, wheat, soybeans, corn, and potatoes—and the results are disturbing. The threats come from rising average temperatures, changes in rainfall patterns, and fragile international shipping infrastructure that is vulnerable to changes in sea level and other weather events.
Researchers all over the world are racing to develop strategies to cope with the new reality. A meeting at the Carter Center in Atlanta in February heard about the expected future catastrophic effects of climate change on human health. The World Health Organization reported that between 2030 and 2050, there will be 250,000 additional deaths a year from heat stress, malnutrition, and infections diseases such as malaria. Worldwide, flooding is the leading cause of weather-related death, but in the US, it’s heat that is the biggest killer, of people and of crops.
A report by the British think-tank Chatham House said that global food security depends on just four crops: maize (or, for my American friends, corn—as with buffalo and bison, the terms are interchangeable in the US), wheat, rice, and soybeans. Maize, wheat, and rice account for 60% of the world’s food energy intake. And soybeans are the biggest source of animal protein feed, making it represent 65% of the global protein feed supply.
Globally, farmers produce more than 700 million tons of wheat every year, but as temperatures rise, wheat yields will go down. Bread, pasta, and other wheat-based foodstuffs are crucial for human nutrition. Researchers at the University of Chicago and the Potsdam Institute for Climate Impact Research looked at the effect of temperature on yields for US crops of soybeans, corn, and wheat, and the results weren’t good. Without carbon reduction, the corn harvest—used for everything from animal feed to some bio fuels—will be cut by 50 per cent. Each day of temperatures above 86 Fahrenheit, the crop yields are reduced by five per cent. Drought will make this threat more severe. With one to three metric tons of water needed to produce one kilo of cereal, farming is one of the largest consumers of water. Judicious irrigation will help reduce this, but the battle for water is going to be one of the most serious of the 21st century. Genetically modified seeds have increased crop yields in the US, but GMO crops are banned in Britain and many European countries, including Russia. Fears of contamination of plant and seed stocks, plus concerns that the world’s seed, and therefore food, supply could be patented by multinational chemical corporations, mean that genetically modified seeds and plants are viewed with suspicion in many places.
Soybeans, another staple crop, will suffer too, according to the study. Using computer simulations, researchers looked at the effect of days with the temperature over 86 degrees F, loss of groundwater, lower levels of rainfall, and population growth impinging on farm land.
Corn is hugely important to North America, particularly as feed for the continent’s huge beef industry. It isn’t just drought that threatens US corn yields. Climate change has also changed the rain patterns, and heavy rain early in the growing season can wash nutrients out of the soil, affecting the young plants. And more moisture in the air means it’s harder to dry the maize before sending it to market: farmers must use more energy to do this, and those costs are passed on to the consumer in the form of higher prices for meat, eggs, and dairy, since much of the corn crop goes to animal feed.
Potatoes, another staple crop in some parts of the world, will benefit from increased carbon dioxide, but, as with other plants, drought and new pests will offset that benefit.
In 2014, a study by Samuel Myers, an environmental health researcher at the Harvard School of Public Health, examined the effect of higher levels of CO2 in the atmosphere on the nutrient levels in food crops. Protein, iron, and zinc levels in wheat, peas, and rice are all lowered by increasing amounts of carbon dioxide in the atmosphere. Seventy-five percent of the world relies on wheat and rice for protein, and even a small reduction in the nutrition obtainable from these sources could have terrible effects on infant and child health. Pulses such as soybeans and lentils are good replacements, and they are rich in iron and proteins, as are leafy green vegetables. However, many of the world’s poorest people can’t always afford to supplement their diets with vegetables.
The combination of climate change and a growing population in sub-Saharan Africa will threaten food security in an already insecure area. There is a minimum temperature for rice crop survival and a maximum temperature for corn crop survival and reaching temperature “tipping points” will drastically affect crops. There are farming methods that can increase yield to match increasing numbers of mouths to feed, but these assume the climate stays stable, and the likelihood of that scenario is small.
Amongst the poorest people affected by climate change are farmers in India. For every one degree of warming, there are 67 more suicides. These people’s livelihood is directly influenced by climate change, and extreme weather affects their crops and therefore their ability to feed themselves. But India’s farmers are also organizing politically, staging protests and lobbying for increased subsidies for crop insurance and for better financing arrangements for seeds and other materials.
The UN is also fighting back against climate change despair. Growing trees around rice fields can help the crops to cope with rising temperatures, according to a new manual produced by the United Nations Food and Agriculture Organization. About half the world’s population gets 30-70% of its nutrition from rice, and most of that rice is grown in Southeast Asia, so any measure that protects that region’s rice harvest is important. Tree-based crops can help farmers diversify their harvest, protect against soil erosion, and provide resources in the event the rice crop is destroyed.
Crop diversity is very important: at one time, human beings used more than 7,000 plants for food and medicine. Now, less than a dozen plant species comprise three-quarters of the world’s food supply. The National Seed Storage Lab in Colorado compared seed varieties today with those at the turn of the last century: there were 500 varieties of cabbage, more than 400 of peas and tomatoes, and 283 varieties of cucumber in 1903. Eighty years later, there were only 28 types of cabbage, 25 varieties of peas, 79 kinds of tomatoes, and 16 types of cucumber. Our food security is in the hands of a few multinational corporations that own the rights to global seed stocks. Their financial interests mean that they are turning perennials into annuals, creating seeds that survive only one season and requiring chemicals, also produced by those companies to flourish.
Much of the research on global food security has focused on technological advances in farming and seed biology, but soil scientist Laura Lengnick argues that the resources should go to farming communities, which have been subsidizing the food supply in the form of long hours and second and third jobs in order to keep farming. Support for regional, eco-friendly food systems is a more realistic system, Lengnick says. This, coupled with encouragement for people to eat local and regional food, will build a sustainable food supply.
A study by the Met Office in Britain has examined what would happen if more than one major growing area were attacked by climate change at the same time. For example, if China and the US—the world’s biggest suppliers of maize—failed simultaneously, then Africa would be plunged into a food crisis.
In some ways, we have already seen what happens when a major supplier of a commodity fails. Russia is the main source of wheat exports for the Arab countries. In 2010, Russia experienced drought, wildfires, and a heat wave, compromising the wheat harvest. We saw the domino effect of these events: Russian crops were threatened by drought; Russia’s supply of wheat diminished; Russia banned the export of wheat; Russia’s traditional markets for wheat, such as Pakistan and Egypt, faced shortages and therefore rising prices; the Pakistani government subsidized food prices to offset the problem, but the Tunisian government didn’t; riots and protests over the price of bread sparked the Arab Spring.
Looking at the global trade in food, Chatham House examined infrastructure at major ports and transit sites, such as the Straits of Malacca. The institute found trade routes vulnerable to climate change, local conflict, and political pressure. It recommended “climate resilient” infrastructure and diversity in food stocks. Chatham House identified 14 “chokepoints” where disaster would threaten global food security. They include the Panama and Suez canals, the Strait of Hormuz, access points to the inland waterways of the US and Brazil, access to the Black Sea ports, and the Strait of Dover.
A projection by researchers at the International Food Policy Research Institute has explored how the world’s growing areas for four major crops—corn, potatoes, rice, and wheat—will shift by 2050. Farmers who are able to diversify will be the most likely to survive, and indeed some regions must diversify because their traditional crops will fail in the new climate system. Northern Europe and North America are likely to maintain their position as food suppliers, and parts of West Africa and Australia that are currently minor agricultural areas will increase in importance, but China and other parts of Asia will face real trouble, according to the model. China, both a huge producer and a huge consumer of global resources, is dealing with the issue another way: by buying up other countries’ food producers, including New Zealand’s biggest meat producer and Australia’s biggest dairy farm.
Having been an apartment dweller most of my adult life, I think it’s very important for everyone to grow as much food as they can, where they can. If you are going to grow from seed, be sure to choose organic, non-GMO, heritage varieties and stay away from the Miracle-Gro. You can grow anything in containers on a balcony—think beyond tomatoes, go beyond potatoes. You can do it all! Your growing area doesn’t need to be perfect: healthy soil and careful nurturing work wonders. Duck and cover really isn’t an option, and those plants on your balcony will help you feel better about the future. Bloom where you’re planted!